Aluminum flakes coated with stearic acid cannot be infiltrated by the base material, and their density is relatively small, thus reducing the downward gravitational force of aluminum scales. On the other hand, with the help of solvent volatilization molecules to the carrier surface to move thrust upward, offsetting the aluminum scales from the weight of the sinking force so that the aluminum flake to the carrier surface floating and oriented near the surface of the paint film to form a layer of opaque silver film, isolated from the air and resin, substrate contact, thus playing a good physical shielding effect.